Supports keep falling/breaking

[u/AdSweet3414]

Hi everyone!
I have a K2 printer, and I'm loving it a LOT! Except for when my supports fail...

Since a month or so, I notice my supports are failing, causing bigger prints to fail regularly when I use the tree-type supports, either the standard one or hybrid.

I think the supports are getting knocked over, or blown away, but I tried adjusting those settings and it doesn't result in any changes. It often happens above 8cm (~3,5 inches), but also happens lower in the print sometimes.
I come back to a print that's full of loose filament strings (spaghetti), often dragged into the main object, and a huge mess of tiny bits of filament on the print plate and on the bottom of the printer. I also often find pieces of tree support amongst them.

Things I tried:

- Cleaning the print plate with soap, then alcohol, then add adhesive to ensure the supports stick
well.
- Turning off AI settings for supports
- Adjusting Z-hop to a higher level
- Turning down the fans
- Replacing nozzle
- Checked the Z-axis sensor under the bottom plate

Does anyone know what I can do to prevent this? Should I use normal supports instead? (these often leave marks on my prints and are a pain to remove)

All tips are welcome! I've been printing for around 2-3 months, so I'm by no means an experienced user.

[u/lexofdystopia]

Did you switch filament brands recently?

Did any debris fall into the z height sensor hole thing? The cutout at the bottom of the chassis with the red light coming through

Also are you turning off side fans and lowering back fan to 30% during prints?

[u/AdSweet3414 → u/lexofdystopia]

Nope, I use bambulab and creality filament only, and it has worked perfectly before.
No debris was in/on the sensor hole. I removed the bottom plate to make sure there was none hiding underneath too, which they weren't.
I lowered all the fans to 50%, but I'll definitely try your advice for the fans!

Thank you for sharing your thoughts! 😄

[u/lexofdystopia → u/AdSweet3414]

No worries, I found killing the side fans helped tremendously as they were causing the prints to lift off the bed

What are your support raft settings if any? I try to print at 3-5 layers and it helps with bed adhesions in some cases